Art of coloring or transforming wood.



UNITED sTATEs PATENT OFFICE.

WILLIAM AUGUSTUS HALL, OF NEW YORK, N. Y., ASSIGNOR'TO AMERICAN MAHOGANYCOMPANY, A CORPORATION OF MAINE.

ART OF COLORING OR TRANSFORMING WOOD.-

No Drawing. Application tiled Kay; 11,

Specification-of Letter-s'ratent. Patented Sept, '7, 1909.

1908. Serial No- 432,222.

To all whom it may concern:

Be it known that I, WILLIAM A. HALL, a citizen of theUnited States,residing at New York, in the county of New York and-State c of New York,have invented or discovered certain new and useful Im rovements in theArt of Coloring or Trans orming Wood, of

which the following is a specification.

This invention or discovery relates to the art of coloring ortransforming wood, so as to produce, from comparatively inexpensivewoods, products closely resembllng black walnut, mahogany or other highprlced woods, both in appearance and texture. e

.The invention or discovery is carried into e-lfect by forcin a coloringmatter into and. throughout the ody of the wood, and in this forcingprocess the coloring matter is largely 5 deposite in the grain cells andmore porou portions of the wood. This'forcing treat ment of the woodleaves the latter more 0 less streaky and some of the harder part of thewoo produce a commercially desirable product it is necessary that theprocess by whi'h the: I coloring matter is forced into the: woodi shouldbe followed by a siibsequent. 'rocess whereby the coloring matter isproper ydif E fused mthe wood. .This difi'usion of the coloring matterin the wood, as described in my application No. 373,152, filed May11,;1907, is-efiected by boiling the wood inthek coloring solution, andpreferably at. com? paratively high temperatures, subsequent to: thecolor-forcing operation; but I have dis-' covered that this ifiusion ofthe coloring matter in the wood may be more economically efl'ected, and;with uite as ood or hot already been permeated by the colorin solugion,instead of boiling the wood, as eretoore.

In carrying the invention or discovery into efli'ect the wood to betreated will referably be in the form of boards or Ian s of anyconvenient .size, and should thoroughly seasoned or dried as any sapor'moisture in the wood tends 'to act as a cushion to prevent thecolorin matter' om being iorced into and throug out the same. "The driedwood is then preferably subjected, in a closed receptacle, to a vacuumaction sufiiciently cordin are but very. slightly colored, and in orderto secure the best results'and ter results, by steaming t e woo whichhas powerful and continued sufliciently long to remove from the woodpractically all of the air therein contained, so as to make the woodabsbrbent or receptive to the coloring solution or fluid to be appliedlater. It is referable, during the vacuum roce'ss, to su ject the woodto a moderate eat of 'approxima'tely 90 'F-., which has a tendenc to 0en the pores and enables. betterwith rawa of the air by the vacuum pump.Any desired coloring solution is then drawn or pumped into thereceptacle, while the vacuum is maintained, until the receptacle is'full, or

may be applied either hot, warm or co (1, ac-

iiigithdrawn by the vacuum process. A ydraulic or other pressure(preferabl O0 to 8 00 pounds to the s uare inch 'porous portions of thewood are impregnated throughout with the coloring solustep of theprocess being\ from two or three hours to tento twelve ours, or more ac--cording to the thickness'or hardness of causes the coloring solution topermeate the wood, but in this coloring-forclni step of the process thecoloring matter will e lar ely wood, as in the "sap wood and theconcentric pm and grain cells, le'avmg, however, more Any suitablecoloring materials or solutions ma be .employed to artificially colorthe woo accordlng to the colors which. it may be desired that the lumbershould have.

imitation mahogany, a li uid coloring matter which will preferabcontainspruce bark extract, hemlock bar extract, or mahogany bark extract, willbe employed. The coloring matter with which the wood s thus impre atedwill then. be diflused 1n the wood steaming the colored wood, and thismay be done either in the cylinder or receptacle in which itvihas beentreated, as

g to. its characteristics, and the solution be taken up more or lessrapidly by "ifiheabsorbent wood from which the air has -lumber undertreatment and the amount of 5? pressure maintained. This high pressure85 the wood therein is fully immersed in the solution. The coloringsolution em loyed {en applied and maintains until the tion, the timerequired for this impregnating 8 vdeposited in the more porous portions.0 the or ess' uncol'ored portions orstreaks and particularly in theheart portions of the wood.

For example, if it be desired to produce an *hardness; an

inbefore referred 35 to the surfaces BO materia-I, to other and less exharder- 60 impre above described, or in a separate chamber orreceptacle, preferably the latter. The

length of time necessary to efl'ect the diffusion of the color bsteaming will depend upon the d thickness of the lumber, but generallyfrom six to fourteen hours will be required; and in this steamingprocess a temperature in the vicinity of 212 F. Wlll preferably bemaintained. This process of eflect- 10 ing the diffusion of "the colorin the wood by steaming has several advantages over the process ofeffecting the diflusion by boiling the wood in the coloring solution, asde-' scribed in my application No. 372,152, hereto! If the woodbe'boiled in the colorin solution sufficiently long and at asuificientfy high temperature to e ect a proper diffusion of thecoloring matter in the wood thecoloring solution itself. is generallyaltered and often destroyed by the heat, thu s 'rendering the surplusllquid unfit for usea second time; but where the surplus coloringsolution is withdrawn from the cylinder immediately after the wood hasbeen thoroughly 2 5 impregnated, and without having been submitted toany high degree of heat, such surplus liquid can be used. for'mpregnating other wood; and it is necessary, i the diffusion beeffected b boiling, to boil the wood in the colorin so ution for thereason that if duce the time during whichthey are occupied by thelumber'as much as possible; and to this end it will be fdundadvantageous to remove the wood, as soon as it has been properlyimpregnated with the coloring pensive receptacles for thesteaming'operatlon to effect a pro er diffusion of the color.

The wood when first removed from thee linder into which it has beenimpregnated by 55.the coloring solution is in a more or less streakycondition, is very largely and sa and thecoloring matter deposited inthe moreporous portlons' of the wood, leaving the cart portions of thewood much less ated with the coloring solution; so that t e sap portionsof the wood are then darker than the heart portions. By the steamingprocess, however, the coloring solution is so diffused throughout thewood that ally scribed for efi'ecting a d1 be done in the same-cyL; 40inder, without removing the wood therefrom.

" same a sorbent the heart portions of the wood may be actudarker thanthe sap portions; while by the methods heretofore employed in ,diflusingthe coloring material by boiling, the sap portions of the wood weredarker than the heart portions'thereof. Moreover as it has been foundnecessary in diffusing the color,

to maintain relatively high temby boiling, peratures of from 225 to 27 5F., or thereabout, the wood itself, as well as the coloring solution, isliable to be more or less damage I by the high temperatures thusemployed; whereas by the steaming rocess herein defi usion of the colorthis liability of in uring the wood by high temperature is entirelyavoided. Moreover it has been ascertained that the steaming processabove described has more effect in eveloping the grain of the wood, andthereby rendering the same/more conspicuous or prominent, than resultsfrom the boillng process which I have previously practiced.

Having thus described my'invention or discovery I claim Letters Patent:w

;1. The herein described process for coloring or transforming wood,consisting in forcing a coloring solution into and throu hout the-moreporous portions of the wood by pressure, and then subsequently diffusingthe coloring material in the wood by subjecting the latter, with thecoloring matter therein, to the action of steam. 7 t

2. The herein described process for coloring or transforming wood,consisting in forcing a coloring solution into and throughout the moreporous portions of the wood by pressure in a close receptacle,withdrawing the surplus coloring solution from said receptacle, and thensubsequently difi'using the co oring material in the wood by subjectingand desire to secure by the latter, with the coloring matter therein,

to the action of steam.

3. The herein described process for coloring or transforming woodconsisting in subjecting the wood to the action of a vacuum in a 'c osedreceptacle for thepurpose of removin the air therefrom and same asorbent, then forcin tion into and'throughout t pressure,

rendering the a coloring solue wood b high the wood, with the coloringsolution therein to -the action of'steam for the purpose of difi'usingthe color in the wood;

4., The herein described process for coloring or'transforr'ning woodconsisting in subjectin the wood to th action of a yacuum a c osedreceptacle or the purpose of removin the airtherefromand rendering thethen forcin a colorin solution into and throughout t e wood 5% highpressure, withdrawing the surplus'coloring solution from saidreceptacle, and then suband then subsequently sub ecting sequentlvsubjecting the wood, with the 001- as derk as or darker than the sapportions 10 orm tion therem, to the action of steam thereof. fog-0t.purpose of difiusing the color in the In testimon whereof I aflix mysignature,

W5 Th h d 4 bed n 1 d in presence 0 two witnesses. 5 e erem escri ert'cia y co ore 4 wood havin the coloring matter therein WILLIAM AUGUSTUSHALL properly di used throughout the wood and Witnesses: the grain cellsfully eveloped, with the V C. M. SWEENEY, harder heart portions of thewood of a color J. D. KLINGE.

